add function to clear specific point

docs/api.md

@@ -202,17 +202,19 @@ YourScreen.endDraw();
 
 #### Description
 
-Clear the screen contents, uses the background colour set in background().
+Clear the screen contents or a specific pixel, uses the background colour set in background().
 
 #### Syntax
 
 ```
 YourScreen.clear()
+YourScreen.clear(x, y)
 ```
 
 #### Parameters
 
-None
+- x: x position of the pixel to clear
+- y: y position of the pixel to clear
 
 #### Returns
 

src/ArduinoGraphics.cpp

@@ -96,6 +96,11 @@ void ArduinoGraphics::clear()
   }
 }
 
+void ArduinoGraphics::clear(int x, int y)
+{
+  set(x, y, _backgroundR, _backgroundB, _backgroundG);
+}
+
 void ArduinoGraphics::fill(uint8_t r, uint8_t g, uint8_t b)
 {
   _fill = true;

src/ArduinoGraphics.h

@@ -51,6 +51,7 @@ class ArduinoGraphics : public Print {
   void background(uint8_t r, uint8_t g, uint8_t b);
   void background(uint32_t color);
   void clear();
+  void clear(int x, int y);
   void fill(uint8_t r, uint8_t g, uint8_t b);
   void fill(uint32_t color);
   void noFill();